What is a 'stopping' and how is it used in mine ventilation?

• A. A permanent barrier to block rockfall.
• B. A temporary wall used to direct airflow and isolate areas.
• C. A device to measure gas concentration.
• D. A type of ventilation fan.

Answer: (B)

Stopping is a temporary barrier placed in mine passages to shape ventilation. It acts to seal off and divide the airways, directing intake air toward the working face and keeping the exhaust on the intended return path. By positioning stoppings, the airflow can be concentrated where it’s needed, reducing short-circuiting through unused drifts and helping manage the dilution and removal of gases and dust. They are especially useful when blasting or performing maintenance, because they allow workers to isolate a section while still maintaining controlled ventilation for the rest of the mine. Stoppings are designed to be movable or adjustable as mining advances, and they’re typically built from bricks, timber, boards, or similar materials. They aren’t measuring devices, not a ventilation fan, and not permanent barriers for rockfall, which is why this description best captures what stoppings do in mine ventilation.